Fig. 1

Representative images of saccular intracranial aneurysm (sIA) walls presenting immunohistochemical staining for LYVE-1 scores 0, 1, 2, 3, 4, and 5 (A). Score 0 represents a wall with no positive staining, score 1 a wall with a few positive cells, score 2 a wall with 1–2 clusters of positive cells, score 3 a wall with several clusters of positive cells, score 4 a wall with scattered positive cells throughout the entire wall, and score 5 a wall with a widespread area of positive staining. Black arrows point down towards the lumen. Intracellular LYVE-1 is indicated with a red arrow and shown as an inset in the image for score 1. Positive staining is brown. Haematoxylin background staining. Scale bar: 100 μm. (B) Distribution of the 36 sIA walls into LYVE-1, podoplanin, VEGFR-3, and Prox1 scores 0–5. Percentages represent the proportion of the scores within the staining